


Cooking With Sherlock

by Topaz_Eyes



Category: Elementary
Genre: Fluff, Gen, Science shenanigans, microwaves and what you can do with them, this is not a fic about cooking
Language: English
Status: Completed
Published: 2019-02-22
Updated: 2019-02-22
Packaged: 2019-11-03 21:24:56
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,562
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17885474
Author URL: https://archiveofourown.org/users/Topaz_Eyes/pseuds/Topaz_Eyes
Summary: “I hope you’re just demonstrating how to make a fruit salad.”





	Cooking With Sherlock

**Author's Note:**

> Many thank yous to Felis for valuable suggestions on an earlier draft. All mistakes are mine. Concrit is always appreciated!

Joan opened the door, her arms overflowing with full grocery bags.

“Sherlock, I’m home,” she called out. “I’ve got groceries.”

There was no reply, however, and she sighed as she set several bags down onto the floor in the hallway. “I could use some help moving these bags to the kitchen,” she added as she doffed her coat and hung it up.

Again, there was no reply. Joan rolled her eyes, wondering where he could be; he’d said he’d be home to help. She picked up the bag of frozen foods, peas and ice cream and chicken, to put away first before they began to thaw. She marched to the kitchen.

Sherlock stood hunched at the kitchen table, his back to her, obviously deep in thought; she heard a telltale scratch of pen on paper.

“There you are,” Joan said. “I have more bags in the hallway, if I could borrow you for a minute – ”

He straightened and turned around, his hands scrunched deep in his pockets, and rocked on the balls of his feet. “Ah, Watson, you’ve returned! Excellent. I should like a witness to my next demonstration.”

“Let me put these in the freezer first,” she said. She felt his impatient gaze bore through her as she opened the freezer door and set the food inside. Only when she finished did she steel herself and turn around to meet the sight before her.

“Hmmm.” It doesn’t seem too bad, she thought at first. She surveyed the bowls of grapes, cherries, and green olives on the table, interspersed with watch glasses holding various pairs of fruit, and sheets of paper covered in Sherlock’s spiky handwriting. “I hope you’re just demonstrating how to make a fruit salad,” she said, “but what are you doing with the olives?”

Sherlock popped a grape into his mouth. “I am confirming a hypothesis,” he announced, crunching through the skin.

Only then did Joan realize the door of their microwave stood wide open, and Joan’s stomach dropped. Oh no. “With our microwave, I see. Do you remember the last time you did that?”

Sherlock’s face lit up with fond remembrance. “Ah, yes. We confirmed that you can indeed calculate the speed of light using marshmallow Peeps, to a most remarkable precision of within one per cent of its exact value. Most gratifying.”

“Yes. And do you remember what happened to the microwave after that?”

Sherlock ignored her, and plucked another grape from the bunch in the bowl. 

“Because I remember. Vividly. You set the Peeps on fire. On fire, Sherlock, and it melted the inside of our microwave beyond repair. We had to throw it out and replace it.”

“I am taking precautions this time to guard against such an outcome.” His hand hovered over the bowl of olives. “As you can see, there is naught an air-whipped sugary confection in sight.” He selected an olive about the same size as the grape, and opened the door of the microwave.

Joan arched a skeptical eyebrow, and pursed her lips to bite back a retort. She noted how a watch glass had already been placed inside on the floor of the chamber. He set the grape and the olive side by side at the middle of the glass so that their respective skins touched.

“Why do I have the feeling this will be even more destructive than the Peeps?” she muttered under her breath.

Sherlock closed the door and nodded at the firm click of the latch. “Right then. One preserved green olive contains twenty-one milligrams of sodium and one point one three milligrams of potassium, compared to zero point zero five milligrams sodium and four point six milligrams potassium per grape, or eighteen point two milligrams potassium per cherry. If I am correct, we should observe a coordinately greater sodium flare compared to the previous attempts with two grapes, or with grapes and cherries.” He punched in one minute on the timer.

Joan glanced sideways at him. “A ‘greater sodium flare’?”

Sherlock pressed the start button. “Watch carefully, Watson,” he exhorted. “This will require only a few seconds to take effect.” He peered inside the oven.

Despite her growing apprehension, Watson joined him and stared at the fruit on the glass. She blinked in surprise as the fruit began to spark. An orange light began to glow right above the point where the olive and grape skins touched.

“The air’s glowing.” She frowned quizzically as a ball of light started to rise above the sparks and into the surrounding air, then quickly dissipated. “Is that – is that – ?”

“Indeed, Watson, that is a plasma discharge.”

The olive and grape bounced apart briefly, cutting off the effect, then rolled back into each other. A second, larger ball of light began to form on contact.

“That’s amazing,” Joan said, shaking her head in admiration. “I didn’t know you could actually generate plasma like that.”

“Nor did I until very recently. Or rather, I was aware that you could produce plasma in this manner, but I learned why it happens only this morning, when I read the relevant paper published in the Proceedings of the National Academy of Sciences. I have been researching alternate, home-based methods to analyze the chemical composition of various substances which do not require the purchase of thousands of dollars worth of expensive and high-maintenance equipment.”

Joan’s curiosity overcame her unease. “So why does it happen?”

Sherlock practically bounced on his toes in delight that she would ask. “As you will remember from your physics classes, microwaves, like all electromagnetic radiation, travel at the speed of light. You will also remember that the speed of light slows down on entering media denser than air. The wavelength of radiation shortens proportionately to the refractive index of the substrate. The refractive index of grapes and similar sized fruit is very high and as it happens, the wavelength shortens to precisely the size of the object. The microwaves become trapped inside the grape and begin to reflect and heat the surrounding medium from the inside out.”

“Microwaves normally heat food from the outside in.”

“Yes, normally that is true, but not in this case. The trapped microwaves generate hot spots inside the fruit due to the buildup of an electromagnetic field. Where two similar-size spheres touch, sufficient energy is concentrated in the EM field, and enough heat is produced at the point of contact, to ionize the air. Hence, plasma.”

“And the colour of the ionized gas reflects the constituents of the spheres?” she asked, thinking back to a particular chemistry class.

“Precisely, Watson.” Sherlock veritably beamed at her, and Joan smiled with satisfaction that her deduction was correct. “The deep yellow colour of the plasma derives from the sodium content of the olive. You missed the cherry experiments earlier while you were procuring our victuals. Those tests produced a lovely shade of lilac plasma, consistent with that drupe’s high level of potassium.” 

The timer reached zero and beeped. Sherlock opened the door and withdrew the watch glass. The grape and the olive had burn marks at the point of contact. He replaced it with a watch glass containing two olives, closed the door, and set the timer.

Within seconds, the air around the olives began to spark wildly and glow.

“That plasma ball is very orange,” Joan mused, entranced by the rising discharge.

“Indeed, it is almost pure sodium at this point,” Sherlock said.

Joan nodded, then blinked and grasped his arm. “Sherlock, that plasma ball is rising very high. It’s almost at the top-- ”

The inside of the microwave flashed bright, and they both jumped back at a very large _pop_.

Joan lunged forward on instinct and unplugged the power cord from the wall receptacle to shut down the microwave. Wisps of smoke seeped out from around the door seal, carrying an acrid odour of burnt plastic that permeated the room.

“Where’s the extinguisher?” she shouted, but Sherlock already had it in hand, nozzle aimed and thumb poised to pull the tab.

No flames escaped, however. They died quickly as they exhausted the oxygen supply in the oven chamber, leaving only a smoky pall inside.

Both Sherlock and Joan coughed, their throats irritated by the escaped smoke. Joan sighed down to the depths of her feet. “And there goes the second microwave this year.”

Sherlock looked at her. “It gave its life for science, Watson. All for a most noble cause.”

She shook her head, already resigned to its fate. “It’s your turn to buy the next one,” she said.

“Perhaps we should acquire two, and we can dedicate one to scientific pursuits.”

Joan nodded. “You know, that is an excellent idea. Leave the kitchen microwave to cooking from now on.”

“I shall begin our quest forthwith.”

“After you help me bring in the rest of groceries from the hall and clean this up.”

“Of course.” He set the extinguisher on the table, pivoted on his heel, and headed straight to the front hall.

Left alone in the kitchen for a moment, Joan watched Sherlock’s retreating back, glanced at the wreckage of what was once their microwave oven, and smiled. Their partnership wouldn’t be what it was without these occasional mishaps. She only wished she had been around to watch the cherries glow. With that thought, she followed him to the hallway to bring the remaining bags in.

**Author's Note:**

> The paper mentioned in the text is “Linking plasma formation in grapes to microwave resonances of aqueous dimers (2019),” Proceedings of the National Academy of Sciences USA, accessed at <https://www.pnas.org/content/early/2019/02/13/1818350116> . Find out how to calculate the speed of light using Peeps at <https://www.npr.org/2015/04/15/399751447/fun-with-physics-finding-the-speed-of-light-with-peeps>.


End file.
